(September 2, 2012)--Sam Stosur withstood a valiant effort from 18-year-old Laura Robson en route to her third consecutive US Open quarterfinal today, 6-4, 6-4 at the US Open today.

Robson saved 8 match points during the second set, and fought back from a break down to get back on serve at 5-4, but when she served to level the match Stosur finally broke through in the ninth.

“It can get a little bit frustrating if you kind of let it get to you,” said Stosur. “I think the more experienced you are, you don't let those things affect you.”

Stosur, who has yet to lose a set in four matches of her first ever Grand Slam title defense, will face World No. 1 Victoria Azarenka in the quarterfinals.

“I have not done well against her in the past,” said Stosur of the No. 1 seed. “I think there's a few things I've learnt over those last few matches. Hopefully I can put all those into play and have a better match and hopefully a very good one.”

Against Robson, Stosur had her mettle tested throughout the one hour, thirty-eight minute affair, but she saved six of eight break points against Robson, and kept her unforced error count to a tidy 24.

Azarenka, who blasted past Georgian Anna Tatishvili on Sunday, has lost ten games in four matches thus far in New York. Azarenka reached her first Grand Slam quarterfinal on her seventh trip to the US Open today, and is enjoying her second Grand Slam as the No. 1 seed.

“She came out and she played really well and she was really aggressive,” Azarenka said of her 22-year-old opponent. “In the end I played really well, but she showed some excellent tennis.”

Azarenka, who won two medals at the 2012 Olympic games, including the gold in mixed doubles, faced nine break points on the afternoon, saving six.

The 23-year-old owns an impressive 6-0 career edge versus her quarterfinal opponent Stosur.

Eleventh-seeded Frenchwoman Marion Bartoli joined Azarenka as a first-time quarterfinalist in New York when she fought back to upset fifth-seeded Petra Kvitova 1-6, 6-2, 6-0.

Bartoli broke Kvitova seven times, and won 25 of 32 points in a lopsided final set, despite having to brush aside two break points.

The results represents a complete turnaround from Kvitova's dominant 6-1, 6-1 performance against Bartoli en route to her first North American hard-court title in Montreal earlier this summer.

Bartoli will play either Nadia Petrova or Maria Sharapova in the quarterfinals.